JP4395066B2 - Suspension device for vehicle - Google Patents

Description

  The present invention relates to a vehicle axle suspension device.

  Suspension devices for vehicles are well known and comprise means for mounting the wheels to a chassis or body including springs and dampers. The device may be used to produce a minimum disturbance to the vehicle body and its contents and, if necessary, a means for redirecting the wheel to steer the vehicle, for example while overcoming a ridge. Allows almost vertical displacement.

  Traditionally, in order to maintain maximum tire contact with the road as it passes through ridges and turns, and maintain control of displacement about the vertical and horizontal axes that can adversely affect vehicle handling. Various means have been used to allow independent movement of individual wheels. For example, the combination of McPherson struts, lower links, torsion bars, double wishbones, radial arms, trailing arms and beam axles are typical well-known examples of such systems.

  Suspensions for single-track vehicles such as motorcycle front wheels are also well known, such as Norton's “Load Holder”, telescopic fork. Vincent's "Girdrallic", Ohlin's "Upside-down" telescopic fork, BMW's "Telelever" fork, Earls It is sold in a variety of designs with registered trademarks, such as the company's leading link forks and the Ariel trailing link forks.

  There are many problems to be solved in the design of the suspension system, and the above-mentioned types are respectively casters, rakes, trails, cambers, toe-ins or toe-outs. out) In combination with settings, an acceptable compromise on handling and control may have been reached.

  More specifically, suspensions that are sufficiently flexible to absorb disturbances and produce a satisfactory ride have problems dealing with dives and squats during vehicle deceleration or acceleration. The rough use of the brake results in a heavy dive at the front end due to weight transfer, leaving very little stroke to absorb the bump with high preload in the spring. This temporarily causes considerable discomfort to passengers due to changes in suspension characteristics. Thus, although anti-dive and anti-squat systems may be desirable features, they can reduce ride comfort and increase manufacturing costs.

  The improved level of performance of modern vehicles and tires makes those problems more serious, and in the case of single-track vehicles such as motorcycles, the motorcycle must be tilted as it goes through the curve to counteract centrifugal forces. And so on. The tilt angle increases with speed or curve radius, and as it passes through the ridges, deflection and twisting of the wheels and chassis can occur, which upsets the handling and control of the vehicle. During high-speed cornering, rotating parts such as wheels and engine flywheels cause precessing of individual gyroscopes, which adversely affect handling, especially a series of sudden front / fork deflections that cause severe wobbling. Can cause the rider to lose control when changing direction through an uneven curve.

  In the majority of motorcycle-qualified designs, the lower parts of the fork, springs, dampers, brake calipers and wheels all move at the same speed, and this unsprung mass is relative when the vehicle is traveling uplift at high speeds. Has a large moment. The forces generated can cause serious stresses and control difficulties, so careful selection of suspension characteristics is necessary and the reduction of unsprung weight should be beneficial as long as they do not compromise the strength or stiffness of the fork. Is well known.

  In many designs, service life is affected by premature wear of the sliding surface, which increases under braking loads and is accelerated by dust adhering to exposed mating elements.

  The above factors affect the ability of the telescopic fork to maintain wheel alignment during linear motion, as gaps between the sliding elements can reduce their stiffness and frictional forces can be uneven. Thus, the strength and rigidity of the fork, axle and its fastening device must be increased to prevent asynchronous movement of the sliding parts, which inevitably increases the unsprung weight.

  Similarly, leading or trailing link forks require loop or bridge elements to provide strength to maintain wheel alignment. This increases the unsprung weight, and since they generally move at the same speed as the wheels, the moments are similar.

  Girder forks also have difficulties in this regard and have the additional problem of inducing high stresses in their mounting bearings, which are relatively long distances from the point of application of the load. Although the fork itself is relatively strong, lateral deflection is easily caused by wear on the mounting bearing.

In accordance with the present invention, upper and lower links of equal swivel length that are pivotally attached to the chassis or body at one end at upper and lower chassis attachment points that are offset from each other and separated by a first distance;
An axle support link positioned at one end and an axle support link attached to opposite ends of the upper and lower links by attachment points separated by a second spacing at the other end;
The first interval is twice the second interval,
The center distance between the axle and the link attachment point is the same as the turning length of the upper link and the lower link,
The device geometry constrains axle / wheel movement in a straight line between chassis attachment points, and the angular displacement of the axle support link exhibits a slight linear displacement at 90 ° with respect to wheel movement. A suspension for a vehicle wheel is provided that concentrates on an axis or center point.

  Certain embodiments of the present invention arrange a lateral torsion bar that has its center of rotation at the fixed axis or focal point of the axle support link and is connected to the axle to provide additional lateral stability. Yes. A disc brake caliper is located on the axle support link to limit the dive, and a small spring and damper system acting around the torsion bar minimizes unsprung weight. The torsion bar also communicates between the opposite wheels of the vehicle and restricts the roll.

  In the case of a single-track vehicle, for example a motorcycle or bicycle, the combination of links, torsion bars, suspensions and dampers that operate in harmony are extremely useful for resisting axle / wheel deflection, especially when traversing a track at high speed. Provides a rigid and relatively lightweight solution, thereby improving stability and control when encountering bumps.

  Further advantages include: Dedicated sealed bearings in pivots where the stiffness and strength of the forks and support elements used in single truck vehicles is of greater importance in terms of weight than is possible with telescopic forks and is dust free and economical to replace Since the wear of moving parts is remarkably eliminated, the sliding friction under load is reduced.

  The present invention will be described below with reference to the accompanying drawings.

  Reference is made to FIG. Links 1 and 2 are connected to substantially rigid fixtures 3 and 4 located on the vehicle body or chassis using dedicated bearings (not shown) and are similar at opposite ends 5 and 6. Is connected to the triangular link 7. The wheel axle 8 is located at the opposite end of the link 7 and depicts a substantially linear motion as indicated by the articulation locus 9 of the links 1, 2 and 7. Centerlines equidistant between points 5 and 6 drawn from the various positions on the track 9 through the axle 8 meet at the point 10 when extended. The latter is designated by the letter “A” and exhibits a relatively short linear motion of 90 degrees on that of the wheel axle 8 and all the angles θ included by the linkage in the central position are equal.

  Reference is made to FIG. This shows a specific embodiment of the present invention applied to the front wheels of a vehicle. The link 7 is shown together with a brake caliper 11 disposed at a predetermined radius from the center of the axle 8. When the brake is applied, the moment due to M1 around the axle generates a deceleration force Fl on the road surface for decelerating the vehicle and a force F2 due to the link mechanism that increases the distance C and lifts the front end of the vehicle. The inertia of the vehicle that resists deceleration acts through its center of gravity that provides load movement ΔW to the front wheels 12. This additional load corresponds to the degree of deceleration, the height of the center of gravity and its position between the front and rear wheels and produces an upward and opposite reaction force F3r. The inertia is also in the horizontal direction due to the horizontal opposing reaction force equal to 0.5F1 at each of the attachment points 3 and 4 and the axle 8 and the links 1 and 2 that move the axle 8 towards the center position of the trajectory 9. Reaction force F1r is also generated. The combined reaction forces F3r and F1r oppose F2, and these forces tend to be balanced in the central stroke of the suspension. The selection of the optimal geometry of the wheel travel along the trajectory 9 together with the correct link proportions and the position of the brake caliper with respect to the focus 10, in this example the suspension characteristic S3 applied to the link 7 by the items 24 and 25. The desired control of the vehicle ride height is produced under deceleration conditions without compromising the vehicle.

Reference is made to FIG. The figure is of a typical vehicle rear wheel assembly in the middle stroke, with links 1 and 2 being pivotally attached to the vehicle body or chassis at pivotable chassis attachment points 3 and 4 at the other end. Are attached in the same way at link attachment points 5 and 6 which can pivot on the link 7. Chassis attachment points 3 and 4 are offset horizontally from link attachment points 5 and 6, and links 1 and 2 have pivot centers that are horizontally offset. A stub axle 8 is attached to the opposite end of the link 7 on which a disc brake caliper 11 is arranged. The link 13 of the torsion bar 14 is attached to the link 7 in the vicinity of the axle 8 compliantly, providing additional lateral stiffness, and the wheels move along the track 9 In effect, slight variations in radial displacement between the link 7 and the torsion bar 14 are possible. The torsion bar 14 is arranged at the coincidence center point 10 described in FIG. A lever arm 15 acts on one end of a strut 16 and the opposite end of the strut is attached to the body at 17. The assembly can be replicated, for example, on the opposite side of the automobile and can be attached to a subframe (not shown) to form a suspension and axle system for the rear wheels of the vehicle.

Reference is made to FIG. This shows a suitable device for the front wheels of a motorcycle. The leg 18 is coupled by a yoke 19 to a pillar 20 that passes through a bearing 21 disposed in a steering head tube 22 that is a part of a motorcycle chassis (not shown). The yoke 23 completes the pivot connection and attachment of the fork to the vehicle, and the shaft is tilted to provide a trail X and rake θ ₂ suitable for maneuvering the vehicle. The fork leg 18 is provided with attachment points 3 and 4, with trailing links 1 and 2 being rotatably connected to them, at their opposite ends to the leading link 7 using dedicated bearings and seals not shown. Similarly connected. Reading links may pass around the axle 8 laterally supported so as to impart slots or legs in the leg 18 18 of the front wheel 12, as a link 7 is attached to the brake caliper 11 it Good. Item 24 is pivotally connected to a link 7 at point 25 and at its opposite end to a spring with a bi-directional damper (not shown) located at or within leg 18. Has been. The device can be replicated on the other side of the wheel and steering head for additional support / control.

Reference is made to FIG. This is a sectional elevation view of one fork leg. An item 24 is pivotally connected to the leading link 7 at point 25 and passes coaxially through the leg 18 where it is rotatably connected to a reciprocating member 26, which is not shown, It has a gear rack 27 which is accommodated in the yoke 19 and meshes with a torsion bar 28 positioned at one end by a bearing. The same fork leg (not shown) is arranged by yokes 19 and 23 parallel to leg 18 on the other side of wheel 12 with axle 8 attached by a similar device of the link. The yokes 19 and 23 can be connected to the vehicle by a post 20 and a bearing 21 (not shown) to provide a means for maneuvering the vehicle. As the wheel 12 moves up and down while traveling on the ridge, the axle 8 shaft and the torsion bar 28 are forced to remain parallel to each other by the gear rack and torsion bar, and any lateral loads that attempt to deflect the wheel. Is strongly resisted.

  FIG. 6 shows the top of a device similar to that of FIG. 5, with two geared torsion bars 28 and 29 meshing with member 26 to provide additional restraint and maintain axle / wheel alignment.

Reference is made to FIG. This is a representation of a suspension similar to that described in FIGS. 4, 5 and 6, but is not limited thereto. It includes a hydraulic strut 16 mounted in a fork leg 18 secured by yokes 19 and 23 so that the assembly pivots about a column 20 mounted on a bearing 21 (not shown) for steering. can do. The strut 16 is a 50:50 flow divider / recombiner (50:50
The gas / oil pressurizing accumulator 30 and the adjustable bump / rebound damper 32 are connected to each other via a flow divider / re-combiner 31. In this configuration, the struts 16 are constrained to work in harmony regardless of the load or pressure on items 31 and / or items 32 and 35 applied to them. The accumulator 30 can be used to change the spring rating by adjusting the pressure, which can be done manually or automatically using a load sensor, CPU 33 and pump 34 (not shown). Bump rebound braking also uses a speed / position sensor 35 to monitor the movement of the item 26 with feedback by the CPU 33 to control the servo motor 36 which adjusts the braking and / or flow accordingly, manually or Either automatically, it can be adjusted externally using an independently adjustable damper 32.

  Reference is made to FIG. This shows a device similar to that of FIG. 7 in which items 31 and 32 are combined into one unit.

6 is a simplified drawing showing link geometry and motion trajectory. Fig. 2 shows a device with a typical reaction force during vehicle deceleration. Fig. 2 is a typical device for a rear wheel suspension of a vehicle in a central stroke. 1 is a side elevation view of a front fork and front wheel of a motorcycle. It is a side elevation view which shows the torsion bar with a gear in a front fork. 1 is a schematic device with a controlled hydraulic suspension.

Claims (12)

A suspension for a vehicle wheel,
Offset from one another, the first interval only separated upper and lower chassis attachment points (3,4) at one end on the same swivel length rotatably mounted to the chassis or body of the vehicle in the link (1) and Down link (2) ,
Positioning the axle (8) of the wheel at one end, the other end in the second interval only separated link attachment point (5,6) the upper link and the axle support link which is attached to the opposite end of the lower link by ( 7)
The first interval is twice the second interval,
Center distance between the link mounting point and the axle is the same as the turning length of the upper link and the lower link,
During use, placement of the suspension system, the movement of the axle and constrained to linearly between the chassis attachment points, center point exhibiting slight rectilinear displacement (A) to 90 ° to the movement of the axle (10) The suspension device , wherein the axle support link is articulated around (10) . The upper and lower chassis attachment points (3, 4) are horizontally offset from the link attachment points (5, 6), and the upper link (1) and lower link (2) are horizontally offset. With pivot centers (3, 4)
The axle comprises a stub axle (8) projecting from one side and the end of the axle support link,
The suspension device is compliantly attached to the other side of the axle support link at one end concentric with the axle center line, and passes between the attachment of the upper link and the lower link, and the shaft is at the center point (10). further comprising, suspended rack apparatus according to claim 1, wherein an additional link that is attached to the torsion bar or tube that matches. The link passes through the leg (18) through the slot,
The upper link (1) and lower link (2) is attached to the leg at either side of the slot,
The sides of the slot provide additional lateral stability and guidance to the links (1, 2) and the wheels (12) attached thereto,
The leg is tilted from a vertical line to provide a rake and trail, and is attached to the chassis by a pivot connection (21) at each end of the leg to steer the vehicle. The suspension described. The leg (18) extends above the upper link (1) and is connected to a single track via a pivotal connection (21) arranged to cover the front wheel upward for maneuvering. 2. Suspension device according to claim 1, wherein upper and lower yokes (23, 19) are provided for attachment to the vehicle chassis .   The configurations of the upper link, the lower link, the axle support link and the leg are arranged on one side of the wheel,
  The suspension is located on the other side of the wheel and attached to the chassis of a single truck vehicle using symmetrical upper and lower yokes (23) and (19) to provide additional stability. The upper link, the lower link, the axle support link, and the second leg, further comprising a second configuration identical to the above-described configuration,
The suspension device according to claim 4. Further comprising a disc brake,
The caliper of the disc brake (11) is fixed to the axle support link (7), reaction force at the time of deceleration of the vehicle is substantially balanced, the moment of unsprung weight is arranged to be minimized, claim The suspension device according to any one of 1 to 5 . One or more torsion bars (28, 29) with gears are rotatably attached to the lower yoke (19) ,
The gear meshes with a fitting rack (27) carved in a reciprocating member (26) disposed in the leg (18) ,
6. Suspension device according to claim 4 or 5 , wherein the reciprocating member (26) is attached to the axle support link (7) via a pivot connection (25) at the lower end to provide a suspension device. Independent spring and / or braking means (32) that vary with speed to change resistance and control the bump rebound movement of the mounted wheel
The suspension device according to claim 1, comprising: Via the axle 5 0:50 flow divider or recombiner (31) of known design which functions irrespective of load and pressure to simultaneously and maintain parallel movement of (8), common gas or oil accumulator (30 ) Hydraulic cylinder (16) coupled to
Including the suspension device according to any one of claims 1 to 8. Independent said damper (33) comprising a speed and / or position sensor (35) connected to a CPU (33) having means (34) for controlling and changing the flow of fluid in the damper to maintain alignment
Including the suspension device according to any one of claims 1 to 9. 11. Suspension device according to any of the preceding claims, further comprising an independently adjustable damper integrated with a 50:50 flow divider or recombiner (31) . External means (33, 34, 35) for independent adjustment of spring rating and bump rebound braking characteristics
Further comprising a suspension device according to any one of claims 1 to 11.

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